Free Unit Converters Online
Metric to imperial and back, instantly: length, weight, temperature and volume.
These free unit converters cover the conversions people make every day, in both directions: cm to inches and inches to cm for heights and screen sizes, kg to lbs and lbs to kg for body weight and luggage, Celsius to Fahrenheit and back for weather and ovens, km to miles for distances and running, meters to feet for rooms and altitude, and ml to oz for recipes and drinks.
Each converter works live: type a number and the result appears as you type, alongside a quick reference table of common values and the formula spelled out, so you can sanity-check the answer or learn the rule of thumb. Everything runs in your browser, free, with no ads between you and the number you came for.
Frequently asked questions
Are these unit converters free?
Yes, completely free with no limits or sign-up. Open one, type your number, and you are done.
How accurate are the conversions?
They use the exact internationally defined factors, for example 1 inch = 2.54 cm and 1 lb = 0.45359237 kg, with results shown to a sensible number of decimals. Any rounding is display-only.
Do the converters work on my phone?
Yes, they are built for quick mobile use: big inputs, instant results, no clutter. Converting a recipe or a weather forecast on your phone takes seconds.
Why are there separate pages for each direction?
Because the situations differ. Someone converting cm to inches is often reading a height or a TV spec; someone going inches to cm is usually measuring for metric instructions. Each page focuses on its own examples, and every converter flips direction with one tap anyway.
Is my input stored anywhere?
No. Conversions happen in your browser and nothing is transmitted. Not that a weight in kg is a state secret, but the answer is still no.